A fundamental principle of nucleic acid molecular hybridization (hybridization for short), a most basic experimental technique in nucleic acid researches, is to allow, based on denaturation and renaturation properties of nucleic acid molecules, DNA (or RNA) fragments of different origins to form hybrid double-stranded molecules in accordance with a base complementary relationship. Hybrid double strands can be formed either by DNA strands or alternatively by RNA and DNA strands. Currently, hybridization has become one of the most frequently used nonradioactive genetic diagnosis technologies in modern molecular biology laboratories. It can be used to test not only gene mutations that would cause canceration or various hereditary diseases (such as thalassemia), but also bacteria, viruses, parasites, and the like that would cause infectious diseases.
Based on different environments in which reactions are performed, hybridization can be divided into solid-phase hybridization and liquid-phase hybridization. And according to different utilization purposes in laboratories, hybridization can include dot (or slot) hybridization, Southern blot hybridization, Northern blot hybridization, cell in situ hybridization, chromosome in situ hybridization, etc.
In solid-phase hybridization, of two nucleic acid strands to participate in a reaction, one is first immobilized onto a solid support, and the other is free in a solution. Depending on different positions of sample molecules to be detected, solid-phase hybridization can be divided into forward hybridization (in which case the sample molecules to be detected are immobilized on a film, while a detecting probe is placed in the solution), and reverse hybridization (in which case the sample molecules to be detected are placed in the solution, while the detecting probe is immobilized on the film). By reverse hybridization, it means to hybridize a labeled sample nucleic acid with an unlabeled and immobilized nucleic acid probe. The advantage of reverse hybridization lies in that multiple nucleic acids in a sample can be simultaneously detected in one hybridization reaction.
Existing reverse hybridization technologies are performed in complicated operations, involving numerous reaction solutions and steps. In particular, when multiple samples are to be detected, the operating time will be remarkably prolonged and errors would easily occur. For example, CN 101768628A discloses a method for detecting nucleic acid point mutations, and specifically discloses a method for detecting nucleic acid point mutations through reverse hybridization performed on a PCR product with an oligonucleotide probe. However, to perform such a method, it is necessary to test a hybridization result with the aid of an expensive fluorescence detection device. This not only involves tedious operations, but is of high costs as well.
As a result, there is an urgent need of a product and a method for rapid detection of a target nucleic acid in a sample.